See below for Teeth & Armor and Parallel Convergence Speculations and much more.
I have some things to clean up and a few hundred newsletters to fold and insert, so I'm off.
Any lurking visitors, feel free to drop a question or two or leave a message.
May the arc be with you! (^u^) Peace be within you ~ salamalaikumsalam ~ shalomelaichemshalom
Really nice free diving video with Tanya Streeter, flying penguins etc.
http://www.youtube.com/watch?v=xsyHt0WHqb4
Wednesday, October 31, 2007
Tuesday, October 30, 2007
Parallel Convergence
Parallel Convergence, Generally speaking:
Anurans: Throat sac buoyancy, vocal mate selection, no tail
Salamanders: no, no, long tail
Hominoids: Laryn. air sac buoyancy, vocal mate selection, no tail
Monkeys: no, no, mid to long tail
Aves: Resp. air sac buoyancy, vocal mate selection, short tail
Reptiles: no, no, long tail
Walruses: Pharyn. air sac buoyancy, vocal mate selection, short tail
Mustelids: no, no (scent), long tail
Pterodons: soft tissue air sac, vocal mate sel.?, reduced tail later
Dinos: no, no, long tail
Anurans: Throat sac buoyancy, vocal mate selection, no tail
Salamanders: no, no, long tail
Hominoids: Laryn. air sac buoyancy, vocal mate selection, no tail
Monkeys: no, no, mid to long tail
Aves: Resp. air sac buoyancy, vocal mate selection, short tail
Reptiles: no, no, long tail
Walruses: Pharyn. air sac buoyancy, vocal mate selection, short tail
Mustelids: no, no (scent), long tail
Pterodons: soft tissue air sac, vocal mate sel.?, reduced tail later
Dinos: no, no, long tail
Teeth & Armor Speculations
[further discussion on this at:]
http://forums.deeperblue.net/674527-post20.html
Introversion of external hair (armor) to internal "teeth"
Baleen whales (blue, humpback, right whales) developed their baleen (whalebone stringy teeth) on the upper jaw, because their fish & mollusc eating ancestors had had walrus-like mustache whiskers which gradually migrated from the upper lip into the upper gums (over a period of a million years), changing from nerve-rich sensory bristles to long net-like filters, straining krill and small fish while allowing water to escape the mouth. (This is one of my hypotheses, haven't seeen any confirmation from others.)
Extroversion of internal teeth to external scales (armor):
Lamphrey (and hagfish?) types lack jaws, but have replaceable teeth which are used to grasp. Is it possible that fish scales derived from multiple teeth replacing (like in sharks, but non-jawed) in a previously non-scaled lamphrey-like ancestor? Various fish scales do resemble teeth in some way, although many have become ultra-smooth for high-speed hydrodynamics. Do fish embryos develop their scales in a cephalo-caudal direction starting at the head? Do primitive scaled fish have more dental-like scales?
Is this a new idea, or has anyone heard of it before? (This is another hypothesis)
Anyway, just seems cool that the opposite actions may have happened in fish and whales.
[Now consider that birds have feathers, which have bloodflow in the plume, do feathers derive from vestigial teeth in early aves which were developing beaks and bills and reducing their ancestral dentition? Are feathers malformed teeth with roots? Where did the beak come from? I don't know.]
DDeden
__________________
"Dive well and come up for more"
The-Arc-of-a-Diver: http://the-arc.wikispaces.com/ / http://the-arc-ddeden@blogspot.com
http://forums.deeperblue.net/674527-post20.html
Introversion of external hair (armor) to internal "teeth"
Baleen whales (blue, humpback, right whales) developed their baleen (whalebone stringy teeth) on the upper jaw, because their fish & mollusc eating ancestors had had walrus-like mustache whiskers which gradually migrated from the upper lip into the upper gums (over a period of a million years), changing from nerve-rich sensory bristles to long net-like filters, straining krill and small fish while allowing water to escape the mouth. (This is one of my hypotheses, haven't seeen any confirmation from others.)
Extroversion of internal teeth to external scales (armor):
Lamphrey (and hagfish?) types lack jaws, but have replaceable teeth which are used to grasp. Is it possible that fish scales derived from multiple teeth replacing (like in sharks, but non-jawed) in a previously non-scaled lamphrey-like ancestor? Various fish scales do resemble teeth in some way, although many have become ultra-smooth for high-speed hydrodynamics. Do fish embryos develop their scales in a cephalo-caudal direction starting at the head? Do primitive scaled fish have more dental-like scales?
Is this a new idea, or has anyone heard of it before? (This is another hypothesis)
Anyway, just seems cool that the opposite actions may have happened in fish and whales.
[Now consider that birds have feathers, which have bloodflow in the plume, do feathers derive from vestigial teeth in early aves which were developing beaks and bills and reducing their ancestral dentition? Are feathers malformed teeth with roots? Where did the beak come from? I don't know.]
DDeden
__________________
"Dive well and come up for more"
The-Arc-of-a-Diver: http://the-arc.wikispaces.com/ / http://the-arc-ddeden@blogspot.com
Tuesday, October 23, 2007
thoughts
Unfinished thoughts to be cont'd.
[QUOTE=naiad;673130]Fascinating. The AAT sounds plausible enough. There are still some things that I don't understand about it though. These are:
Nostrils which cannot be closed. Most aquatic mammals close their nostrils when diving. No animal uses a noseclip or pinches its nose, and few use sinus flooding.[/QUOTE]
True. First, our ancestors went through two different stages.
The first (amphibious) was transitional from a tarsier-like mammal with tail to a vertical-oriented part-time awkward bipedal upright wader/walker/floater (amphibious tree-frog-like) which lost the tail due to large laryngeal air sacs that inflated upon cool-water immersion due to a gasp-like reaction, allowing plucking foods on the water surface and shallow snails etc. but which did not swim well and did not dive at all, about 15 to 5 million years ago, along coastal lowland forests often flooded, this included all ape ancestors. But while human ancestors remained there, other apes moved inland into Asia and African into various swamps and riverine gallery forests, moving deeper and deeper into tropical rainforests, and because of large inland predators became more and more tree dependent, and when walking on the ground, tended to knucklewalk for more speed and stability. About 5 million years ago, when the chimps finally permanently split, chimps followed the path that a million years previously gorillas had gone, into the Rift valley and Congo. At this time all hominoids had air sacs, used for floating vertically with the face out of water, and for calling loudly. So now only the human ancestors were left at the seashores, they never knucklewalked (but the infants kneecrawled on the soft sands), they climbed easy-to-climb fig trees, mangroves and coconut palms, but not the tall forest trees. They adapted more to coastal pocket beaches surrounded by cliffs with caves and rockshelters, and slowly became better surface swimmers but not divers, mostly beachcombing and peeling molluscs from mangroves and rocks at low tide, in addition to fruits and seabird eggs. At this time, the nose was shaped like a baby's pug nose, the bell jar shape keeping water out during the rare dunkings. Since the nose was usually kept above the water by the air sacs, there was no natural selection for closable nostrils. This was completely unlike other aquatic animal ancestors, none of which had inflated laryngeal air sacs keeping the nose above water.
The second phase (aquatic) was only human ancestors, not apes, and seems to have occurred about 3 - 1 million years ago, when they gained a fat layer under the skin, the air sac was reduced to a vestige, lost most of the fur coat, but retained hydrodynamic hair in the voids of the body (throat, neck, armpits and pubic areas), and changed from surface floating and plucking to deeper diving, and eventually at some point developed a backfloating-diving cycle somewhat like a sea otter. Up until then, the pug-nose shaped like a bell jar was enough to keep water out of the airways as long as the mouth was closed or the tongue or velum closed the airway, this worked fine at the surface with the inflated air sac just under the throat, but only allowed plucking food below at arm's length. The air sac interfered with face submersion, and was slowly selected against, allowing deeper dipping, while the nose was selected for longer length. so during backfloating breathing was done through the nose when head was tilted back.
Until this time, the nostrils would not have been selected for closing, since the air sacs always kept the face above water. But with deeper diving, came water pressure problems and breath holding, which no ape had ever had before.
[QUOTE]
Poor underwater vision. Although some people are apparently better off than others, including tribes who dive regularly, most aquatic animals have much better underwater vision than we do. Those which do not, or live in murky water, have other adaptations such as long whiskers (seals), echolocation (dolphins and whales), lateral line (aquatic amphibians).[/QUOTE]
[QUOTE=naiad;673130]Fascinating. The AAT sounds plausible enough. There are still some things that I don't understand about it though. These are:
Nostrils which cannot be closed. Most aquatic mammals close their nostrils when diving. No animal uses a noseclip or pinches its nose, and few use sinus flooding.[/QUOTE]
True. First, our ancestors went through two different stages.
The first (amphibious) was transitional from a tarsier-like mammal with tail to a vertical-oriented part-time awkward bipedal upright wader/walker/floater (amphibious tree-frog-like) which lost the tail due to large laryngeal air sacs that inflated upon cool-water immersion due to a gasp-like reaction, allowing plucking foods on the water surface and shallow snails etc. but which did not swim well and did not dive at all, about 15 to 5 million years ago, along coastal lowland forests often flooded, this included all ape ancestors. But while human ancestors remained there, other apes moved inland into Asia and African into various swamps and riverine gallery forests, moving deeper and deeper into tropical rainforests, and because of large inland predators became more and more tree dependent, and when walking on the ground, tended to knucklewalk for more speed and stability. About 5 million years ago, when the chimps finally permanently split, chimps followed the path that a million years previously gorillas had gone, into the Rift valley and Congo. At this time all hominoids had air sacs, used for floating vertically with the face out of water, and for calling loudly. So now only the human ancestors were left at the seashores, they never knucklewalked (but the infants kneecrawled on the soft sands), they climbed easy-to-climb fig trees, mangroves and coconut palms, but not the tall forest trees. They adapted more to coastal pocket beaches surrounded by cliffs with caves and rockshelters, and slowly became better surface swimmers but not divers, mostly beachcombing and peeling molluscs from mangroves and rocks at low tide, in addition to fruits and seabird eggs. At this time, the nose was shaped like a baby's pug nose, the bell jar shape keeping water out during the rare dunkings. Since the nose was usually kept above the water by the air sacs, there was no natural selection for closable nostrils. This was completely unlike other aquatic animal ancestors, none of which had inflated laryngeal air sacs keeping the nose above water.
The second phase (aquatic) was only human ancestors, not apes, and seems to have occurred about 3 - 1 million years ago, when they gained a fat layer under the skin, the air sac was reduced to a vestige, lost most of the fur coat, but retained hydrodynamic hair in the voids of the body (throat, neck, armpits and pubic areas), and changed from surface floating and plucking to deeper diving, and eventually at some point developed a backfloating-diving cycle somewhat like a sea otter. Up until then, the pug-nose shaped like a bell jar was enough to keep water out of the airways as long as the mouth was closed or the tongue or velum closed the airway, this worked fine at the surface with the inflated air sac just under the throat, but only allowed plucking food below at arm's length. The air sac interfered with face submersion, and was slowly selected against, allowing deeper dipping, while the nose was selected for longer length. so during backfloating breathing was done through the nose when head was tilted back.
Until this time, the nostrils would not have been selected for closing, since the air sacs always kept the face above water. But with deeper diving, came water pressure problems and breath holding, which no ape had ever had before.
[QUOTE]
Poor underwater vision. Although some people are apparently better off than others, including tribes who dive regularly, most aquatic animals have much better underwater vision than we do. Those which do not, or live in murky water, have other adaptations such as long whiskers (seals), echolocation (dolphins and whales), lateral line (aquatic amphibians).[/QUOTE]
Friday, October 19, 2007
Celebes Sea: rare marine species
(Photo not linked to article)
http://scienceblogs.com/pharyngula/2007/10/friday_cephalopod_free_octy.php
http://news.yahoo.com/s/ap/20071016/ap_on_sc/new_marine_species
Project leader Dr. Larry Madin said Tuesday that U.S. and Philippine scientists collected about 100 different specimens in a search in the Celebes Sea south of the Philippines. Madin, of the Massachusetts-based Woods Hole Oceanographic Institution, said the sea is at the heart of the "coral triangle" bordered by the Philippines, Malaysia and Indonesia — a region recognized by scientists as having a high degree of biological diversity.
The deepest part of the Celebes Sea is 16,500 feet. The team was able to explore to a depth of about 9,100 feet using a remotely operated camera. "This is probably the center where many of the species evolved and spread to other parts of the ocean, so it's going back to the source in many ways," Madin told a group of journalists, government officials, students and U.S. Ambassador Kristie Kenney and her staff. The project involved the Woods Hole Oceanographic Institution and National Geographic Magazine in cooperation with the Philippine government, which also provided the exploration ship. The expedition was made up of more than two dozen scientists and a group from National Geographic, including Emory Kristof, the underwater photographer who was part of the team that found the wreckage of the Titanic in 1985. The group returned to Manila on Tuesday after spending about two weeks in the Celebes Sea off Tawi-Tawi, the Philippines southernmost provincial archipelago nearly 700 miles south of Manila.
Madin said the specimens they collected included several possibly newly discovered species. One was a sea cucumber that is nearly transparent which could swim by bending its elongated body. Another was a black jellyfish found near the sea floor. The most striking creature found was a spiny orange-colored worm that had 10 tentacles like a squid, Madin said. "We don't know what it is ... it might be something new," he said. He said it would take "a few more weeks" of research to determine whether the species are newly discovered. He expects to release a report by early next month.
Madin said the Celebes Sea, being surrounded by islands and shallow reefs, is partially isolated now and may have been more isolated millions of years ago, leading scientists to believe that "there may be groups of organisms that have been contained and kept within" the basin since then.
Monday, October 15, 2007
Simplest Proof
http://edition.cnn.com/2007/TECH/science/10/17/early.seafood.ap/index.html
Editor's Summary: Nature | 18 October 2007 | Life was a beach
It's been suggested that the first thing Homo sapiens did once he and she had evolved was head for the beach. This is demonstrated in dramatic fashion by a series of discoveries in Middle Pleistocene sediments from a South African sea cave near Pinnacle Point. The finds suggest that by around 164,000 years ago, the residents were on a diet that included shellfish — the earliest evidence for the exploitation of coastal resources by some 40,000 years. There is also evidence that they used pigments such as red ochre for symbolic behaviour. This was at a time when the world was going through a cool, dry spell, and Africa was mostly desert. Perhaps this environmental stress drove small bands of hunter–gatherers down to the sea in search of new food
sources and lifestyles.
News and Views: Palaeoanthropology: The coast in colour
A South African cave overlooking the Indian Ocean was apparently a desirable residence for early humans. The site has provided rich evidence for the early use of colour and marine resources.
Sally McBrearty & Chris Stringer
doi:10.1038/449793a Full Text | PDF (584K)
Letter: Early human use of marine resources and pigment in South Africa during the Middle Pleistocene
Curtis W. Marean, Miryam Bar-Matthews, Jocelyn Bernatchez, Erich Fisher, Paul Goldberg, Andy I. R. Herries, Zenobia Jacobs, Antonieta Jerardino, Panagiotis Karkanas, Tom Minichillo, Peter J. Nilssen, Erin Thompson, Ian Watts & Hope M. Williams
doi:10.1038/nature06204
Re: 1998 AAT videos
http://www.youtube.com/watch?v=VFsgtLxALac
http://www.youtube.com/watch?v=jTPQUU0KxMY
http://www.youtube.com/watch?v=kKSBWHGA5KI
http://www.youtube.com/watch?v=-88v2pLSYCk
http://www.youtube.com/watch?v=OnPJBuWPt0Y
A fine presentation!
Thanks to Algis for putting these videos on You-Tube for all to see.
Good to see Sir Alister Hardy, Dr. Morgan, Dr. Verhaegen, Dr. Tobias, Dr. Brain, Dr. Crawford, and more contributing to our knowledge of the human ancestral condition in relation to water.
DD
Editor's Summary: Nature | 18 October 2007 | Life was a beach
It's been suggested that the first thing Homo sapiens did once he and she had evolved was head for the beach. This is demonstrated in dramatic fashion by a series of discoveries in Middle Pleistocene sediments from a South African sea cave near Pinnacle Point. The finds suggest that by around 164,000 years ago, the residents were on a diet that included shellfish — the earliest evidence for the exploitation of coastal resources by some 40,000 years. There is also evidence that they used pigments such as red ochre for symbolic behaviour. This was at a time when the world was going through a cool, dry spell, and Africa was mostly desert. Perhaps this environmental stress drove small bands of hunter–gatherers down to the sea in search of new food
sources and lifestyles.
News and Views: Palaeoanthropology: The coast in colour
A South African cave overlooking the Indian Ocean was apparently a desirable residence for early humans. The site has provided rich evidence for the early use of colour and marine resources.
Sally McBrearty & Chris Stringer
doi:10.1038/449793a Full Text | PDF (584K)
Letter: Early human use of marine resources and pigment in South Africa during the Middle Pleistocene
Curtis W. Marean, Miryam Bar-Matthews, Jocelyn Bernatchez, Erich Fisher, Paul Goldberg, Andy I. R. Herries, Zenobia Jacobs, Antonieta Jerardino, Panagiotis Karkanas, Tom Minichillo, Peter J. Nilssen, Erin Thompson, Ian Watts & Hope M. Williams
doi:10.1038/nature06204
Re: 1998 AAT videos
http://www.youtube.com/watch?v=VFsgtLxALac
http://www.youtube.com/watch?v=jTPQUU0KxMY
http://www.youtube.com/watch?v=kKSBWHGA5KI
http://www.youtube.com/watch?v=-88v2pLSYCk
http://www.youtube.com/watch?v=OnPJBuWPt0Y
A fine presentation!
Thanks to Algis for putting these videos on You-Tube for all to see.
Good to see Sir Alister Hardy, Dr. Morgan, Dr. Verhaegen, Dr. Tobias, Dr. Brain, Dr. Crawford, and more contributing to our knowledge of the human ancestral condition in relation to water.
DD
Blog Action Day: Environmental Stability
Today is World Environmental Sustainability Day on the Blogosphere.
Links to sites:
http://www.blogactionday.org/
http://www.blogactionday.org/my
Replacement of primary rainforest ecosystem with large-scale oil palm plantation improves short-term economic development but may result in silt erosion of coral reefs and major reduction of biodiversity. What is the optimal path of development? Ecosystem collapse benefits no-one, forest preserves benefit future generations sustainably.
http://www.youtube.com/watch?v=Qv8NlidN2wg&NR=1
Ecosystemic Society Collapse Symptoms: (As the world turns)
http://www.logic-fu.com/archive/archive/collapse.html
Links to sites:
http://www.blogactionday.org/
http://www.blogactionday.org/my
Replacement of primary rainforest ecosystem with large-scale oil palm plantation improves short-term economic development but may result in silt erosion of coral reefs and major reduction of biodiversity. What is the optimal path of development? Ecosystem collapse benefits no-one, forest preserves benefit future generations sustainably.
http://www.youtube.com/watch?v=Qv8NlidN2wg&NR=1
Ecosystemic Society Collapse Symptoms: (As the world turns)
http://www.logic-fu.com/archive/archive/collapse.html
Saturday, October 13, 2007
10 year old Chinese girl "dolphin swimming"
http://webcenters.netscape.compuserve.com/whatsnew/gallery.jsp?floc=g-wnew_huang_li1&gname=wnew_huang_li&pi=4&grurl=http%3A%2F%2Fwww.google.com%2Fsearch%3Fq%3Dhuang%2Bli%2Bdaosheng%26ie%3Dutf-8%26oe%3Dutf-8%26aq%3Dt%26rls%3Dcom.ubuntu%3Aen-US%3Aofficial%26client%3Dfirefox-a&photo=1&xad=true
http://www.cnn.com/2007/WORLD/asiapcf/10/04/china.swimmmer.ap/index.html?eref=rss_mostpopular
hands and feet bound, "dolphin swimming"
She intends to cross the English Channel this way I guess.
I'd think it would be better if the bindings were a simple loop, that she could remove.
3 hours in the river, 3 km / 1.8 miles downstream.
Thursday, October 11, 2007
Earth travelers
African mega-droughts:
http://www.physorg.com/news111083381.html
10.10.07
davina.quarter...@oxon.blackwellpublishing.com
Environmental setting of human migrations in the circum-Pacific Region
A new study by Kevin Pope of Geo Eco Arc Research and John Terrell of The Field Museum adds insight into the migration of anatomically modern humans out of Africa and into Asia less than 100,000 years before present (BP). The comprehensive review of human genetic, environmental, and archaeological data from the circum-Pacific region supports the hypothesis, originally based largely on genetic evidence, that modern humans migrated into eastern Asia via a southern coastal route. The expansion of modern human populations into the circum-Pacific region occurred in at least four pulses, in part controlled by climate and sea level changes in the Late Pleistocene and Holocene epochs. The initial "out of Africa" migration was thwarted by dramatic changes in both sea level and climate and extreme drought in the coastal zone. A period of stable climate and sea level
45,000-40,000 years BP gave rise to the first major pulse of migration, when modern humans spread from India, throughout much of coastal southeast Asia, Australia, and Melanesia, extending northward to eastern Russia and Japan by 37,000 years BP.
The northward push of modern humans along the eastern coast of Asia stalled north of 43°N latitude, probably due to the inability of the populations to adjust to cold waters and tundra/steppe vegetation. The ensuing cold and dry Last Glacial period, ~33,000-16,000 year BP, once again brought dramatic changes in sea level and climate, which caused abandonment of many coastal sites. After 16,000 years BP, climates began to warm, but sea level was still 100 m below modern levels,
creating conditions amenable for a second pulse of human migration into North America across an ice-free coastal plain now covered by the Bering Sea.
The stabilization of climate and sea level in the early Holocene (8,000-6,000 years BP) supported the expansion of coastal wetlands, lagoons, and coral reefs, which in turn gave rise to a third pulse of coastal settlement, filling in most of the circum-Pacific region. A slight drop in sea level in the western Pacific in the mid-Holocene (~6,000-4,000 year BP), caused a reduction in productive coastal
habitats, leading to a brief disruption in human subsistence along the then densely settled coast. This disruption may have helped initiate the last major pulse of human migration in the circum-Pacific region, that of the migration to Oceania, which began about 3,500 years BP and culminated in the settlement of Hawaii and Easter Island by 2000-1000 years BP.
http://www.physorg.com/news111083381.html
10.10.07
davina.quarter...@oxon.blackwellpublishing.com
Environmental setting of human migrations in the circum-Pacific Region
A new study by Kevin Pope of Geo Eco Arc Research and John Terrell of The Field Museum adds insight into the migration of anatomically modern humans out of Africa and into Asia less than 100,000 years before present (BP). The comprehensive review of human genetic, environmental, and archaeological data from the circum-Pacific region supports the hypothesis, originally based largely on genetic evidence, that modern humans migrated into eastern Asia via a southern coastal route. The expansion of modern human populations into the circum-Pacific region occurred in at least four pulses, in part controlled by climate and sea level changes in the Late Pleistocene and Holocene epochs. The initial "out of Africa" migration was thwarted by dramatic changes in both sea level and climate and extreme drought in the coastal zone. A period of stable climate and sea level
45,000-40,000 years BP gave rise to the first major pulse of migration, when modern humans spread from India, throughout much of coastal southeast Asia, Australia, and Melanesia, extending northward to eastern Russia and Japan by 37,000 years BP.
The northward push of modern humans along the eastern coast of Asia stalled north of 43°N latitude, probably due to the inability of the populations to adjust to cold waters and tundra/steppe vegetation. The ensuing cold and dry Last Glacial period, ~33,000-16,000 year BP, once again brought dramatic changes in sea level and climate, which caused abandonment of many coastal sites. After 16,000 years BP, climates began to warm, but sea level was still 100 m below modern levels,
creating conditions amenable for a second pulse of human migration into North America across an ice-free coastal plain now covered by the Bering Sea.
The stabilization of climate and sea level in the early Holocene (8,000-6,000 years BP) supported the expansion of coastal wetlands, lagoons, and coral reefs, which in turn gave rise to a third pulse of coastal settlement, filling in most of the circum-Pacific region. A slight drop in sea level in the western Pacific in the mid-Holocene (~6,000-4,000 year BP), caused a reduction in productive coastal
habitats, leading to a brief disruption in human subsistence along the then densely settled coast. This disruption may have helped initiate the last major pulse of human migration in the circum-Pacific region, that of the migration to Oceania, which began about 3,500 years BP and culminated in the settlement of Hawaii and Easter Island by 2000-1000 years BP.
Monday, October 8, 2007
The arc of a diver
Lucia: Dive reflex not always helpful? I have been doing dry and pool {dive} training for a long time now, and my dry breath holding apnea performance is always significantly better than in the pool. I have tried to work out what the reason is, but nothing fully explains it. What a useless reflex, I don't know how it could possibly be good in any situation to gasp when falling into cold water.
DD: It helps to understand how the body reacts to temperature and pressure changes.
Feet first: gasp, wading in cool water
Face first: MDR, diving in cool water
It's actually the same reflex, maximizing oxygen retention, but face-first shuts off the inhalation phase, while feet-first exaggerates the inhalation phase.
Your best MDR response might be this approach:
(with a buddy at poolside watching and estimating time, not a small crowded pool)
1) NO wetsuit, just swim suit, warm and dry, no nose/ear plugs/mask/cap.
2) PLAN only ONE dive, (afterwards hit the hot shower, then dry and leave).
3) NO breathe up, just walk to the edge of deep end, casually deflate lungs while leaning forward, and pushing gently off into the water, entering face-first with arms down at your sides, to between 1/2 to 2 meters deep, glide down and forward until stopping, then casually but with strength, kick a few times while gliding hydrodynamically, then, when ready to climb, [*see note below] bring your arms forwards and SLOWLY power stroke laterally at sides (no more kicking) diagonally or vertically up to the surface, turn onto your back and inhale a few slow moderate breaths (not deeply) while laying flat like a board on the surface relaxing, backstoke over to the edge and climb up and leave pool. You did it. Shower, dry, go home, forget it.
4) It's not the length of time or distance, it's the technique, 20 seconds submersed is fine.
5) That night, dream the dive again, let the experience come back, learn from it subconsciously while sleeping, adjust little things (slower or faster kick, hear echoes under water, sense difference between surface temp. and depth temp. etc.).
6) Repeat pool dives often, after the first day, 2nd and 3rd dives are ok, but stay focussed on technique, hydrodynamics and sensing conditions. No more dry/wet statics until normal dives are smooth enough to make a dolphin smile.
* Assuming no lane intrusions and not close to wall, close eyes during ascent and allow face skin to inform you of your position. Your ears know the depth and body orientation via the eardrums and the 3 semicircular canals of the inner ear, your hair/forehead/eyebrows/eyelids/eyelashes know the speed and the difference between water and air temperature and pressure, rely on this sensitivity. Once in backfloating position and ready to scull to the edge, only then open the eyes and go.
Lucia: Maybe I will try the one-dive approach, with a buddy. I am still a bit scared of getting into cold water, because for me the gasp reflex happens even if I put my face only in the water. It is not so bad if I take a deep breath and hold it, and much worse with empty lungs.
DD: I fully empathise with the dislike of cold water immersion. The reason I mentioned it was because I assume your available pools aren't really warm and the pumps keep moving the water around. The ideal would be very very warm at the surface (6" 15cm) and quite cool just above the pool floor, with the water almost still and thermally stratified, like in a sunlit tropical lagoon completely surrounded by reefs.
By breathing up, and then filling the lungs with air, the body's sensors read "low CO2 so plentiful O2", and keep burning O2 at a regular aerobic non-MDR pace.
Then when the CO2 rises due to the fast O2 burning, contractions or air hunger starts.
OTOH, having the MDR/gasp occur right away with empty lungs forces O2 conservation, burns O2 slowly and builds CO2 slowly. This registers in your mind as discomfort because you haven't gradually habituated to it. The same physiological gasp that tries to suck in air to the lungs is actually pumping O2 from the extremities. By sealing the mouth and nose (with tongue in back), the coldwater gasp has nowhere to come from but the blood cells and muscle cells rich in O2 in the limbs, biochemically kicking them to move faster towards the core to ease the pH differential.
Lucia: Interesting. That makes sense. I remember that when I was a kid, if I was outside and there was a cold wind blowing, I would get an uncontrollable apnea reflex, which was unpleasant but bearable. It must have lasted for a few seconds. It still happens occasionally, but much less. It was very similar to the feeling I now get when I put my face in cold water.
DD: Right, the fast combined thermal and pressure change on the face, and also in the throat triggers the reflex.
When you hold your breath with full-lungs, I think you are getting about 1/2 of this effect due to air pressure on baroreceptors in the mouth/nose/throat/lungs.
When you did empty-lung breath hold, that 1/2 effect was missing, so you only felt the struggle phase, without the benefit of the 1/2 effect.
What I've been saying, is that by first being warm and dry, and knowing that soon you will again be very warm in the shower afterwards, then, casually diving in slightly cool water, that if you relax and accept the "switch-over" discomfort, knowing that it's just a temporary adjustment your body makes as it "becomes one with water" (no longer bothering to carry this huge "bubble" of excess air in the lungs down under the surface), and let your body feel the water as you glide through, and limbs smoothly power you along, and then rising up again to the surface, you are fully aware and sensitive to your immediate environment, and gracefully exchange the gift of air. Upon contacting the surface, you will want to exhale, but don't push it out, just exchange it gratefully.
As you climb out of the pool, your body which was adapted to the cool water during the dive, is now warming up due to the aerobic metabolism required to deal with moving in regular terrestrial gravity, so do a brief stretch of arms and legs and trunk, and a moderate aerobic breathe-up (no forced inhale, just a yawn), this should give a blush or flushed face and a tiny sweat reaction (the opposing reflex of the gasp), and then go take a warm shower and dry off.
Actually, I think that both of these reflexes release biochemicals into the bloodstream including micro-doses of endorphins and natural steroids, that help relax during stress.
Anyway, like I said, if something doesn't sound or feel right, don't do it, take time to figure out what's happening. Don't rush a dive, relax a dive. Those super-fast dolphin's ancestors 50 million years ago were once very slow divers too, as were our ancestors at the seashores 1 million years ago. It takes time. Dive with dolphins, backfloat with sea otters, blow bubbles with koi, breathe.
The thermoreceptors and baroreceptors of the face, mouth, throat are involved in the early part of the MDR empty lung dive.
The chemoreceptors in various places where blood flows through are involved in the next part of the dive. They are affected by the pH changes, as CO2 accumulates, diaphragmatic contractions and/or air hunger due to higher CO2 concentration gets stronger. It is the MDR gasp all over again, but this time triggered internally at the core, rather than externally at the skin surface of the face.
Since most people aren't used to making their blood send O2 more efficiently, we tend to get a "shock" when getting contractions. But the contractions simply move O2 towards the lungs. By propelling while matching these contractions to a whole body undulation or kick or arm stroke makes them less noticeable and might even add some extra oomph with no additional energy or oxygen consumption.
DD: It helps to understand how the body reacts to temperature and pressure changes.
Feet first: gasp, wading in cool water
Face first: MDR, diving in cool water
It's actually the same reflex, maximizing oxygen retention, but face-first shuts off the inhalation phase, while feet-first exaggerates the inhalation phase.
Your best MDR response might be this approach:
(with a buddy at poolside watching and estimating time, not a small crowded pool)
1) NO wetsuit, just swim suit, warm and dry, no nose/ear plugs/mask/cap.
2) PLAN only ONE dive, (afterwards hit the hot shower, then dry and leave).
3) NO breathe up, just walk to the edge of deep end, casually deflate lungs while leaning forward, and pushing gently off into the water, entering face-first with arms down at your sides, to between 1/2 to 2 meters deep, glide down and forward until stopping, then casually but with strength, kick a few times while gliding hydrodynamically, then, when ready to climb, [*see note below] bring your arms forwards and SLOWLY power stroke laterally at sides (no more kicking) diagonally or vertically up to the surface, turn onto your back and inhale a few slow moderate breaths (not deeply) while laying flat like a board on the surface relaxing, backstoke over to the edge and climb up and leave pool. You did it. Shower, dry, go home, forget it.
4) It's not the length of time or distance, it's the technique, 20 seconds submersed is fine.
5) That night, dream the dive again, let the experience come back, learn from it subconsciously while sleeping, adjust little things (slower or faster kick, hear echoes under water, sense difference between surface temp. and depth temp. etc.).
6) Repeat pool dives often, after the first day, 2nd and 3rd dives are ok, but stay focussed on technique, hydrodynamics and sensing conditions. No more dry/wet statics until normal dives are smooth enough to make a dolphin smile.
* Assuming no lane intrusions and not close to wall, close eyes during ascent and allow face skin to inform you of your position. Your ears know the depth and body orientation via the eardrums and the 3 semicircular canals of the inner ear, your hair/forehead/eyebrows/eyelids/eyelashes know the speed and the difference between water and air temperature and pressure, rely on this sensitivity. Once in backfloating position and ready to scull to the edge, only then open the eyes and go.
Lucia: Maybe I will try the one-dive approach, with a buddy. I am still a bit scared of getting into cold water, because for me the gasp reflex happens even if I put my face only in the water. It is not so bad if I take a deep breath and hold it, and much worse with empty lungs.
DD: I fully empathise with the dislike of cold water immersion. The reason I mentioned it was because I assume your available pools aren't really warm and the pumps keep moving the water around. The ideal would be very very warm at the surface (6" 15cm) and quite cool just above the pool floor, with the water almost still and thermally stratified, like in a sunlit tropical lagoon completely surrounded by reefs.
By breathing up, and then filling the lungs with air, the body's sensors read "low CO2 so plentiful O2", and keep burning O2 at a regular aerobic non-MDR pace.
Then when the CO2 rises due to the fast O2 burning, contractions or air hunger starts.
OTOH, having the MDR/gasp occur right away with empty lungs forces O2 conservation, burns O2 slowly and builds CO2 slowly. This registers in your mind as discomfort because you haven't gradually habituated to it. The same physiological gasp that tries to suck in air to the lungs is actually pumping O2 from the extremities. By sealing the mouth and nose (with tongue in back), the coldwater gasp has nowhere to come from but the blood cells and muscle cells rich in O2 in the limbs, biochemically kicking them to move faster towards the core to ease the pH differential.
Lucia: Interesting. That makes sense. I remember that when I was a kid, if I was outside and there was a cold wind blowing, I would get an uncontrollable apnea reflex, which was unpleasant but bearable. It must have lasted for a few seconds. It still happens occasionally, but much less. It was very similar to the feeling I now get when I put my face in cold water.
DD: Right, the fast combined thermal and pressure change on the face, and also in the throat triggers the reflex.
When you hold your breath with full-lungs, I think you are getting about 1/2 of this effect due to air pressure on baroreceptors in the mouth/nose/throat/lungs.
When you did empty-lung breath hold, that 1/2 effect was missing, so you only felt the struggle phase, without the benefit of the 1/2 effect.
What I've been saying, is that by first being warm and dry, and knowing that soon you will again be very warm in the shower afterwards, then, casually diving in slightly cool water, that if you relax and accept the "switch-over" discomfort, knowing that it's just a temporary adjustment your body makes as it "becomes one with water" (no longer bothering to carry this huge "bubble" of excess air in the lungs down under the surface), and let your body feel the water as you glide through, and limbs smoothly power you along, and then rising up again to the surface, you are fully aware and sensitive to your immediate environment, and gracefully exchange the gift of air. Upon contacting the surface, you will want to exhale, but don't push it out, just exchange it gratefully.
As you climb out of the pool, your body which was adapted to the cool water during the dive, is now warming up due to the aerobic metabolism required to deal with moving in regular terrestrial gravity, so do a brief stretch of arms and legs and trunk, and a moderate aerobic breathe-up (no forced inhale, just a yawn), this should give a blush or flushed face and a tiny sweat reaction (the opposing reflex of the gasp), and then go take a warm shower and dry off.
Actually, I think that both of these reflexes release biochemicals into the bloodstream including micro-doses of endorphins and natural steroids, that help relax during stress.
Anyway, like I said, if something doesn't sound or feel right, don't do it, take time to figure out what's happening. Don't rush a dive, relax a dive. Those super-fast dolphin's ancestors 50 million years ago were once very slow divers too, as were our ancestors at the seashores 1 million years ago. It takes time. Dive with dolphins, backfloat with sea otters, blow bubbles with koi, breathe.
The thermoreceptors and baroreceptors of the face, mouth, throat are involved in the early part of the MDR empty lung dive.
The chemoreceptors in various places where blood flows through are involved in the next part of the dive. They are affected by the pH changes, as CO2 accumulates, diaphragmatic contractions and/or air hunger due to higher CO2 concentration gets stronger. It is the MDR gasp all over again, but this time triggered internally at the core, rather than externally at the skin surface of the face.
Since most people aren't used to making their blood send O2 more efficiently, we tend to get a "shock" when getting contractions. But the contractions simply move O2 towards the lungs. By propelling while matching these contractions to a whole body undulation or kick or arm stroke makes them less noticeable and might even add some extra oomph with no additional energy or oxygen consumption.
Monday, October 1, 2007
VISUALIZE
Flight of the Malaysian fruit bat
Xray of nose and paranasal sinuses of Chinese lady
http://www.sciencemag.org/cgi/content/full/317/5846/1858
Go to the site linked and enlarge the photos by clicking on them. Very unique "art".
Xray of nose and paranasal sinuses of Chinese lady
http://www.sciencemag.org/cgi/content/full/317/5846/1858
Go to the site linked and enlarge the photos by clicking on them. Very unique "art".
Sunday, September 2, 2007
Plucking-Diving-Dugouts-Trading-Trucking
DD: my response to: "No aquatic apes in Morris, Minnesota"
PZ is up in Morris, MN, which is just to the left of the famed big "C" of lakes (see map) that make up the majority of the "Land of 10,000+ lakes". Morris happens to be on a railroad line and at the intersection of a bunch of highways, so there's plenty of traffic, otherwise it'd be just another farm town (with a fabulous university).
Before the days of the locomotive and wheeled vehicles, and before the bow and arrow and atlatl were developed, and before horses were domesticated, humans could travel by foot or by dugout. Dugouts provided relatively safe access to remote inland areas where the big cats were kings and (waterways where) crocs and hippos resided. Before the development of the dugout, the most successful inland hominids were those that could climb above the cats and crocs, which is why the inland (apes)/apiths had curved phallanges and ancient Homo didn't.
Dugouts allowed easy access to extra weapons including slingstone pebbles used as ballast and spears used as push-poles, heavy cumbersome tools to carry by foot but easily by boat. Travel and trade eventually expanded from coastal settlements inland. Before dugouts, the inland was a dangerous place for a hominid that couldn't climb well or run fast and had only thrusting spears.
Dugouts, originally crafted by butted handaxes from waterside bent hollow tree trunks, were the first (cargo capable) "pickup trucks", and are still used worldwide in a more engineered form. A fisherman in one caught a coelecanth off the beach in Sulawesi in May. Ribbed watercraft (birchbark canoes, plank boats, umiaks) came later, partly due to the need for portaging.
Dugouts were the transitional technology enabling a coastal hominid (family) to move upstream and inland (w/o climbing adaptations), changing from daily diving and plucking sessile seafoods (where hydrodynamics were significant) to more terrestrial hunting and "dry" fishing using nets and spears.
I see no reason to think that acacia would have been chosen over other waterside trees for early dugout construction, though it may have been used later if others were unavailable, perhaps with fire to core it out.
http://www.earthwatch.org/site/apps/nl/content2.asp?c=dsJSK6PFJnH&b=2...
(contributed by Lee Olsen at Sci.Anthro.Paleo)
A team of Spanish archaeologists, led by Dr. Manuel Dominguez-Rodrigo, from the Complutense University of Madrid, found residues of wood on the working edges of stone handaxes found in the region. The stone tools also show clear damage due to having been used in heavy-duty
activities. These important findings push the appearance of human woodworking back by 1 million years, and will be reported in the April/May issue of the Journal of Human Evolution. "This is the oldest evidence of woodworking in human evolution," said Dominguez-Rodrigo. "The remains belonging to Acacia trees are proof that early humans had wooden utensils, such as spears and digging sticks, which very likely enabled them to have the technology necessary to become successful hunters."
The area of Peninj contains some of the oldest archaeological sites in
the world with Acheulian tools. Most of the fossil fauna discovered by the Spanish team belong to animals that suggest a very open and dry savanna environment. Equids (like modern zebras), antilopini (like modern gazelles) and alcelaphini (like modern wildebeest) constitute most of the animals discovered. The fossil pollen discovered also indicates a very open landscape dominated by grasslands and a smaller number of trees among which Acacia is the best represented. Some plant residues discovered (called phytoliths) show that the type of grass most represented is a short grass that grows in very open and dry ecosystems."
DD: As might be expected, acacia for push-pole thrusting spears. Whether acacia was used for crafting (early) dugouts is much less certain. Cutting soft wood would presumably leave less traces than hard wood on handaxes. Push-pole thrusting spears would be a consumable disposable
item, easily replaced, a dugout less so. Thanks for the confirmation Lee!
Diving (My response to Seth's Human evolution post)
I agree with much of the AAT, but see it as part of life in a generalised coastal tropical habitat. Occupational specialization in later humans fits with my interpretation of butted hand axes as both butchering tools and woodcrafting tools used to construct the first dugout boats from hollow bent trees at waterside. These dugouts were the 'first cargo pickup trucks on the aquatic superhighway" that allowed trade and settlements upstream inland in areas formerly
dominated by the big cat predators, and allowed relatively safe easy transport of people including babies, with slingstone pebbles as ballast in the bottom for stability, and push-pole thrusting spears propelling and spare throwing spears bunched aside like arrows in a quiver. Further development of boats included thinner lighter dugouts and later portageable ribbed skin kayaks, birchbark canoes and plank sailboats on the sea of galilee 20,000 years ago.
The words Tectonic, Technical, Technology have the root Tek, which is Greek for carpenter or craftsman. I think it derived from the sound of stone "tick-ticking" against stone to make a hand axe and other simple tools. Other languages around the world have similar sounding words for crafting tools, which suggest great antiquity. (Chip or chop are other variations of it.)
The hand in primates (and even more in anthropoids) was selected for plucking loosely hanging fruits in angiosperm trees, which had previously been the long held domain of fruit bats and frugivorous birds. Plucking allowed the changes in the jaws and dental structure,
which allowed the brain to enlarge later.
This combined with greater vertical climbing and posture produced a more stable bipedal locomotion, as seen in the gibbon and spider monkey. Bipedal wading doesn't cause dry land bipedalism (see wetland apes which wade on 2 legs but walk on 4, while gibbons are bipedal on the ground but never wade), but it does reinforce an already bipedal habit.
Most likely the combination of fruit tree climbing, wading for molluscs in mangroves, shore cliff climbing for seabird eggs, coconut palm climbing, beachcombing for turtle eggs, vertical floating (with inflated laryngeal air sac) while plucking aquatic vegetation all combined to further the upright stance in hominoids and resulted in the complete loss of the tail. Later, the ancestors of the Great apes expanded inland along gallery forests staying arboreal and becoming more quadrupedal when on the ground, while ancient Homo erectus improved swimming and changed from vertical floating to horizontal backfloating (losing the lar. throat air sac but gaining a layer of skin fat) resulting in greater hydrodynamic linearity, thermoinsulation and oxygen breath holding abilities and becoming a more adept diver for shellfish and crustaceans.
I envision them diving as male-female pairs alternating dives, while the younger males acted as area patrol guards/gangs (also competing for deeper diving/spearfishing, tree climbing for coconuts and figs, and various small game hunting) and younger females as babysitters and
beachcombers at the shore. Later the use of hollow logs and driftwood as floats in waters with crocs or sharks began the emergence of the most primitive vehicular industry, shells pebbles and stone tools used to make simple dugouts.
DDeden
http://www.blog.sethroberts.net/2007/08/10/my-theory-of-human-evolution-planet-earth-edition/
http://scienceblogs.com/pharyngula/2007/08/nope_no_aquatic_apes_found_in.php
PZ is up in Morris, MN, which is just to the left of the famed big "C" of lakes (see map) that make up the majority of the "Land of 10,000+ lakes". Morris happens to be on a railroad line and at the intersection of a bunch of highways, so there's plenty of traffic, otherwise it'd be just another farm town (with a fabulous university).
Before the days of the locomotive and wheeled vehicles, and before the bow and arrow and atlatl were developed, and before horses were domesticated, humans could travel by foot or by dugout. Dugouts provided relatively safe access to remote inland areas where the big cats were kings and (waterways where) crocs and hippos resided. Before the development of the dugout, the most successful inland hominids were those that could climb above the cats and crocs, which is why the inland (apes)/apiths had curved phallanges and ancient Homo didn't.
Dugouts allowed easy access to extra weapons including slingstone pebbles used as ballast and spears used as push-poles, heavy cumbersome tools to carry by foot but easily by boat. Travel and trade eventually expanded from coastal settlements inland. Before dugouts, the inland was a dangerous place for a hominid that couldn't climb well or run fast and had only thrusting spears.
Dugouts, originally crafted by butted handaxes from waterside bent hollow tree trunks, were the first (cargo capable) "pickup trucks", and are still used worldwide in a more engineered form. A fisherman in one caught a coelecanth off the beach in Sulawesi in May. Ribbed watercraft (birchbark canoes, plank boats, umiaks) came later, partly due to the need for portaging.
Dugouts were the transitional technology enabling a coastal hominid (family) to move upstream and inland (w/o climbing adaptations), changing from daily diving and plucking sessile seafoods (where hydrodynamics were significant) to more terrestrial hunting and "dry" fishing using nets and spears.
I see no reason to think that acacia would have been chosen over other waterside trees for early dugout construction, though it may have been used later if others were unavailable, perhaps with fire to core it out.
http://www.earthwatch.org/site/apps/nl/content2.asp?c=dsJSK6PFJnH&b=2...
(contributed by Lee Olsen at Sci.Anthro.Paleo)
A team of Spanish archaeologists, led by Dr. Manuel Dominguez-Rodrigo, from the Complutense University of Madrid, found residues of wood on the working edges of stone handaxes found in the region. The stone tools also show clear damage due to having been used in heavy-duty
activities. These important findings push the appearance of human woodworking back by 1 million years, and will be reported in the April/May issue of the Journal of Human Evolution. "This is the oldest evidence of woodworking in human evolution," said Dominguez-Rodrigo. "The remains belonging to Acacia trees are proof that early humans had wooden utensils, such as spears and digging sticks, which very likely enabled them to have the technology necessary to become successful hunters."
The area of Peninj contains some of the oldest archaeological sites in
the world with Acheulian tools. Most of the fossil fauna discovered by the Spanish team belong to animals that suggest a very open and dry savanna environment. Equids (like modern zebras), antilopini (like modern gazelles) and alcelaphini (like modern wildebeest) constitute most of the animals discovered. The fossil pollen discovered also indicates a very open landscape dominated by grasslands and a smaller number of trees among which Acacia is the best represented. Some plant residues discovered (called phytoliths) show that the type of grass most represented is a short grass that grows in very open and dry ecosystems."
DD: As might be expected, acacia for push-pole thrusting spears. Whether acacia was used for crafting (early) dugouts is much less certain. Cutting soft wood would presumably leave less traces than hard wood on handaxes. Push-pole thrusting spears would be a consumable disposable
item, easily replaced, a dugout less so. Thanks for the confirmation Lee!
Diving (My response to Seth's Human evolution post)
I agree with much of the AAT, but see it as part of life in a generalised coastal tropical habitat. Occupational specialization in later humans fits with my interpretation of butted hand axes as both butchering tools and woodcrafting tools used to construct the first dugout boats from hollow bent trees at waterside. These dugouts were the 'first cargo pickup trucks on the aquatic superhighway" that allowed trade and settlements upstream inland in areas formerly
dominated by the big cat predators, and allowed relatively safe easy transport of people including babies, with slingstone pebbles as ballast in the bottom for stability, and push-pole thrusting spears propelling and spare throwing spears bunched aside like arrows in a quiver. Further development of boats included thinner lighter dugouts and later portageable ribbed skin kayaks, birchbark canoes and plank sailboats on the sea of galilee 20,000 years ago.
The words Tectonic, Technical, Technology have the root Tek, which is Greek for carpenter or craftsman. I think it derived from the sound of stone "tick-ticking" against stone to make a hand axe and other simple tools. Other languages around the world have similar sounding words for crafting tools, which suggest great antiquity. (Chip or chop are other variations of it.)
The hand in primates (and even more in anthropoids) was selected for plucking loosely hanging fruits in angiosperm trees, which had previously been the long held domain of fruit bats and frugivorous birds. Plucking allowed the changes in the jaws and dental structure,
which allowed the brain to enlarge later.
This combined with greater vertical climbing and posture produced a more stable bipedal locomotion, as seen in the gibbon and spider monkey. Bipedal wading doesn't cause dry land bipedalism (see wetland apes which wade on 2 legs but walk on 4, while gibbons are bipedal on the ground but never wade), but it does reinforce an already bipedal habit.
Most likely the combination of fruit tree climbing, wading for molluscs in mangroves, shore cliff climbing for seabird eggs, coconut palm climbing, beachcombing for turtle eggs, vertical floating (with inflated laryngeal air sac) while plucking aquatic vegetation all combined to further the upright stance in hominoids and resulted in the complete loss of the tail. Later, the ancestors of the Great apes expanded inland along gallery forests staying arboreal and becoming more quadrupedal when on the ground, while ancient Homo erectus improved swimming and changed from vertical floating to horizontal backfloating (losing the lar. throat air sac but gaining a layer of skin fat) resulting in greater hydrodynamic linearity, thermoinsulation and oxygen breath holding abilities and becoming a more adept diver for shellfish and crustaceans.
I envision them diving as male-female pairs alternating dives, while the younger males acted as area patrol guards/gangs (also competing for deeper diving/spearfishing, tree climbing for coconuts and figs, and various small game hunting) and younger females as babysitters and
beachcombers at the shore. Later the use of hollow logs and driftwood as floats in waters with crocs or sharks began the emergence of the most primitive vehicular industry, shells pebbles and stone tools used to make simple dugouts.
DDeden
http://www.blog.sethroberts.net/2007/08/10/my-theory-of-human-evolution-planet-earth-edition/
http://scienceblogs.com/pharyngula/2007/08/nope_no_aquatic_apes_found_in.php
Thursday, August 30, 2007
Salam Merdeka /|\ Selam Merdeka
1776 Independence US
1957 Merdeka Malaysia
Selamat Hari Merdeka Malaysiaku
http://news.bbc.co.uk/2/hi/asia-pacific/6970348.stm
Live Free /|\ Dive Free
1957 Merdeka Malaysia
Selamat Hari Merdeka Malaysiaku
http://news.bbc.co.uk/2/hi/asia-pacific/6970348.stm
Live Free /|\ Dive Free
Monday, August 27, 2007
Human head hair & hydrodynamics
Olympic swim suit: http://scienceblogs.com/pharyngula/2008/08/honey_wheres_my_supersuit.php
Straight hair shafts are ( ) round (didn't change from our long ago ancestors that lived and dove for shellfish on tropical pocket beaches), while curly hair was later derived (the hair shaft became oval (curly) or () elliptical, not round) which protected people who lived inside tropical rain forests from lice (which carry typhus disease), lice lay their eggs (nits) in hair, but in very curly hair the eggs can't stay attached. People with curly head hair also have curly body hair (but straight eyelashes).
Beard, armpit and pubic hair are called coarse secondary hair, it is fluffy and developed during the diving era, where it gave a smooth rounded linear hydro-dynamic profile when diving, filling the body voids in places that skin fat couldn't fill. Below there is more info.
----- Original Message -----
From: DDeden
To: AAT@yahoogroups.com
Sent: Monday, August 27, 2007 5:38 AM
There are many arguments that can be made for and against AAT, but the one that convinced me was the long straight/wavy head hair for hydrodynamics. Since no other aquatic animal has very long hair, it is not a comparable trait, but I can think of no other reason for 1+ m long head hair except fluid diving and swimming in a mammal which did not become very tube-shaped (unlike most other aquatics) because of pre-existing sessile plucking during feeding. The plucking had existed
during the LCA H-oid as part of the vertical floating/wading and tree food collection, the brain had hard-wired for that feeding style, allowing the face and jaw to reduce prognathism, compared to monkeys and other primates. Modern humans have even less prognathism, indicating even stronger plucking feeding (and tool use).
Plucking => jaws shrink (Homo) or enlarge (boisie nut cracker).
Long head hair is fine at the shores, ok on the savanna but useless, while in the trees it is a problem. People living in tropical rainforests tend to have frizzy hair and/or cut it short or tie it up in some way.
I've written on the frizzy inland hair re. lice and typhus, the main reason I'm sure it's correct is that people with frizzy/nappy hair have straight eyelashes. How could they have started with curly eyelashes? They are more derived biologically than slightly curled or straight haired people, regarding tropical inland adaptation.
So therefore, I doubt that H aq was a large tropical island dweller, as on Papua or Borneo or Taiwan rich in mangroves and muck.
They weren't on coral atolls (due to mineral deficiency) either.
However small to medium volcanic islands with encircling reefs around, perhaps the archipelagos along the Pacific ring of fire, the Maldives and Andamans and Afar, with reduced large cat predators, with some silt/soil for mangroves and fruit trees but not large swamps which crocs favor, and warm reef-protected lagoons which sharks don't favor.
DDeden
I've written on the frizzy inland hair re. lice and typhus, the main reason I'm sure it's correct is that people with frizzy/nappy hair have straight eyelashes. How could they have started with curly eyelashes? They are more derived biologically than slightly curled or straight haired people, regarding tropical inland adaptation.
DD
Interesting thought but it's possible to select for straight hair in some places and curly in others e.g. pubic hair is curly in straight-haired people.
Elaine Morgan
East Asians tend to have relatively straight hair everywhere, although the beard, axillary and pubic hair is less straight and more kinked (but by no means curly). All other people have beard, axillary and pubic hair of similar kinky/straight texture, which is even less straight than East Asians, but still not curled at all.
Inland tropical people with very curly (frizzy/nappy) head hair have very curly body hair, but their beard, axillary and pubic hair is comparatively much more straight, and their eyelash hair is straight.
This indicates that the LCA Homo had straight head hair, straight eyelash hair, straight mustache hair (like orangs), and straight but slightly kinked (not curled) beard, axillary and pubic hair.
I think that kinked-straight hair in the beard, axillary and pubic areas is a result of hydrodynamic selection, since it fills the voids of the body better than straight hair does during swimming. I don't think it's form is due to better odor release, though maybe secondarily.
Therefore, I'd expect that other apes lack this special beard, axillary and pubic form of hair, or only have it to a slight degree.
AFAIK, all people born with the hyperhirsute super-hairy syndrome have straight/wavy hair, never frizzy/nappy nor blonde hair. This occurs most often in Asians (though still very rare). There's a photo of a Chinese guy with this condition in AAT photos, it is probably similar to the LCA Homo hair condition.
That frizzy/nappy hair was ancestral to Hs fits no data whatsoever AFAIK. Our Homo ancestors may have been (shoreside) African, but did not have frizzy/nappy hair.
I suggest that frizzy hair is a recently derived trait in Hs not older than 200ka and more likely 60ka, resulting from the improvement of dugout boats, nets and weapons allowing people into the interior in relative safety. The Khoisan seem to be an intermediate, I don't know precisely their situation, but since they do no diving, likely they were isolated from coastal living at some point, perhaps they were the
rift descendants. Dugouts are widespread all throughout the tropics, that is how I think the tropical rainforest Africans survived away from the sea, safer from [predators but not against pathogens, making increased eccrine sweat and curled hair very important selective traits. Dry air = wavy hair. Humid air = curly hair. Sea diving = straight hair with kinked straight beard/ axil/pubic hair.
DDeden
Straight hair shafts are ( ) round (didn't change from our long ago ancestors that lived and dove for shellfish on tropical pocket beaches), while curly hair was later derived (the hair shaft became oval (curly) or () elliptical, not round) which protected people who lived inside tropical rain forests from lice (which carry typhus disease), lice lay their eggs (nits) in hair, but in very curly hair the eggs can't stay attached. People with curly head hair also have curly body hair (but straight eyelashes).
Beard, armpit and pubic hair are called coarse secondary hair, it is fluffy and developed during the diving era, where it gave a smooth rounded linear hydro-dynamic profile when diving, filling the body voids in places that skin fat couldn't fill. Below there is more info.
----- Original Message -----
From: DDeden
To: AAT@yahoogroups.com
Sent: Monday, August 27, 2007 5:38 AM
Hydrodynamic Head Hair => AAT
There are many arguments that can be made for and against AAT, but the one that convinced me was the long straight/wavy head hair for hydrodynamics. Since no other aquatic animal has very long hair, it is not a comparable trait, but I can think of no other reason for 1+ m long head hair except fluid diving and swimming in a mammal which did not become very tube-shaped (unlike most other aquatics) because of pre-existing sessile plucking during feeding. The plucking had existed
during the LCA H-oid as part of the vertical floating/wading and tree food collection, the brain had hard-wired for that feeding style, allowing the face and jaw to reduce prognathism, compared to monkeys and other primates. Modern humans have even less prognathism, indicating even stronger plucking feeding (and tool use).
Plucking => jaws shrink (Homo) or enlarge (boisie nut cracker).
Long head hair is fine at the shores, ok on the savanna but useless, while in the trees it is a problem. People living in tropical rainforests tend to have frizzy hair and/or cut it short or tie it up in some way.
I've written on the frizzy inland hair re. lice and typhus, the main reason I'm sure it's correct is that people with frizzy/nappy hair have straight eyelashes. How could they have started with curly eyelashes? They are more derived biologically than slightly curled or straight haired people, regarding tropical inland adaptation.
So therefore, I doubt that H aq was a large tropical island dweller, as on Papua or Borneo or Taiwan rich in mangroves and muck.
They weren't on coral atolls (due to mineral deficiency) either.
However small to medium volcanic islands with encircling reefs around, perhaps the archipelagos along the Pacific ring of fire, the Maldives and Andamans and Afar, with reduced large cat predators, with some silt/soil for mangroves and fruit trees but not large swamps which crocs favor, and warm reef-protected lagoons which sharks don't favor.
DDeden
I've written on the frizzy inland hair re. lice and typhus, the main reason I'm sure it's correct is that people with frizzy/nappy hair have straight eyelashes. How could they have started with curly eyelashes? They are more derived biologically than slightly curled or straight haired people, regarding tropical inland adaptation.
DD
Interesting thought but it's possible to select for straight hair in some places and curly in others e.g. pubic hair is curly in straight-haired people.
Elaine Morgan
East Asians tend to have relatively straight hair everywhere, although the beard, axillary and pubic hair is less straight and more kinked (but by no means curly). All other people have beard, axillary and pubic hair of similar kinky/straight texture, which is even less straight than East Asians, but still not curled at all.
Inland tropical people with very curly (frizzy/nappy) head hair have very curly body hair, but their beard, axillary and pubic hair is comparatively much more straight, and their eyelash hair is straight.
This indicates that the LCA Homo had straight head hair, straight eyelash hair, straight mustache hair (like orangs), and straight but slightly kinked (not curled) beard, axillary and pubic hair.
I think that kinked-straight hair in the beard, axillary and pubic areas is a result of hydrodynamic selection, since it fills the voids of the body better than straight hair does during swimming. I don't think it's form is due to better odor release, though maybe secondarily.
Therefore, I'd expect that other apes lack this special beard, axillary and pubic form of hair, or only have it to a slight degree.
AFAIK, all people born with the hyperhirsute super-hairy syndrome have straight/wavy hair, never frizzy/nappy nor blonde hair. This occurs most often in Asians (though still very rare). There's a photo of a Chinese guy with this condition in AAT photos, it is probably similar to the LCA Homo hair condition.
That frizzy/nappy hair was ancestral to Hs fits no data whatsoever AFAIK. Our Homo ancestors may have been (shoreside) African, but did not have frizzy/nappy hair.
I suggest that frizzy hair is a recently derived trait in Hs not older than 200ka and more likely 60ka, resulting from the improvement of dugout boats, nets and weapons allowing people into the interior in relative safety. The Khoisan seem to be an intermediate, I don't know precisely their situation, but since they do no diving, likely they were isolated from coastal living at some point, perhaps they were the
rift descendants. Dugouts are widespread all throughout the tropics, that is how I think the tropical rainforest Africans survived away from the sea, safer from [predators but not against pathogens, making increased eccrine sweat and curled hair very important selective traits. Dry air = wavy hair. Humid air = curly hair. Sea diving = straight hair with kinked straight beard/ axil/pubic hair.
DDeden
Thursday, August 23, 2007
Linguistic links
PIE-PAU *enxm *duxm *texm *kexwrm *pfwm *xnxm *xeptm *ahxwm *nahxwm *dexm
(nxm sounds like engksum , pfwm sounds like fum, with e & u in midst of short and long sound)
Not sure where the Latin 5 quinque (French cinque ~ zank) came from
Not sure where the PAu 10 sa-puluq (Samoan safulu) came from, perhaps inverted from pukul (beat); (one hand can punch (panj = 5 fingers) need 2 hands to clap = 10 fingers)
"Humans are merely aquaterrestuarborealistically derived from a more primitive (in the scientific sense) basal primate" a naturalist might say, though I don't recall having heard it...yet.
(nxm sounds like engksum , pfwm sounds like fum, with e & u in midst of short and long sound)
Not sure where the Latin 5 quinque (French cinque ~ zank) came from
Not sure where the PAu 10 sa-puluq (Samoan safulu) came from, perhaps inverted from pukul (beat); (one hand can punch (panj = 5 fingers) need 2 hands to clap = 10 fingers)
"Humans are merely aquaterrestuarborealistically derived from a more primitive (in the scientific sense) basal primate" a naturalist might say, though I don't recall having heard it...yet.
Wednesday, August 22, 2007
Medium sized Islands with reefs, lagoons
Bucky Fuller right on reefs, probably wrong on atolls
Atolls are Pacific islands where the central volcano has eroded down below the
sea but the coral reefs are above sea level. Although there is
plentiful seafood and coconuts, iron and copper are deficient.
Rainwater dissolves the lime of the exposed reef, calcium carbonates
erodes but lack the volcanic soils that non-atoll islands and
continents possess. So people that live on atolls have poor skeletal
growth, susceptible to osteoporosis, unless supplemented from abroad.
Ancient Homo erectus shows many semi-aquatic traits, and was noted for
having very thick very dense skeletons, not porous skeletons.
It is likely they lived along shores where mangroves lived, rich
silted deposits in tidal waters, where fruit bats roosted, dropping
their seed rich feces, thus planting new fruit trees near the shores.
These mangroves require Iron and copper just like people do, and do
not grow as well on isolated atolls. The result is that mangroves and fruit trees
grow poorly on atolls, but very well on volcanic isles and continental
coasts surrounded by reefs.
Ancient mankind lived on isles near the Indo-Pacific coasts, rich in soil, fruit, fruit-bats, sea-birds, shellfish...going back and forth on occasion (during lower sea levels of the ice ages) by walking/wading/swimming/dugouts to continents
where the big predator cats lived.
Big cats couldn't survive on small islands, crocs might but avoid the
surf and sandy beaches, while sharks risk getting land-locked when
entering the shallow tidal lagoons. I think that slowly dugouts
eventually allowed human ancestors to over-run the continents through
the river systems into the savannas, with sturdy hulls protecting them
and storing their weapons of mass destruction (push-pole thrusting
spears, ballast of large pebbles for throwing), with tensile nets and
woven reed baskets slowly being developed.
--- In AAT@yahoogroups.com, "Dick Fischbeck" wrote:
>
> here are Fuller's words:
>
> http://www.bfi.org/EveryThing/everything_i_know3.htm
>
>
>
> [�]
>
> Unquestionably the great barrier reefs there break those
> enormous waves, and inside those lovely
> lagoons are full of fish and all kinds of eatables, and the very,
> very easy shoaling lovely sands
> and you could climb in and out of that as a baby practically, and
> on the shores coconuts falling
> down full of milk, and all kinds of things to eat, and no big
> animals to eat you so I came to the
> conclusion life being born naked and helpless, probably on the
> coral atolls, then began to have
> experience after experience with that water
>
> [...]
Atolls are Pacific islands where the central volcano has eroded down below the
sea but the coral reefs are above sea level. Although there is
plentiful seafood and coconuts, iron and copper are deficient.
Rainwater dissolves the lime of the exposed reef, calcium carbonates
erodes but lack the volcanic soils that non-atoll islands and
continents possess. So people that live on atolls have poor skeletal
growth, susceptible to osteoporosis, unless supplemented from abroad.
Ancient Homo erectus shows many semi-aquatic traits, and was noted for
having very thick very dense skeletons, not porous skeletons.
It is likely they lived along shores where mangroves lived, rich
silted deposits in tidal waters, where fruit bats roosted, dropping
their seed rich feces, thus planting new fruit trees near the shores.
These mangroves require Iron and copper just like people do, and do
not grow as well on isolated atolls. The result is that mangroves and fruit trees
grow poorly on atolls, but very well on volcanic isles and continental
coasts surrounded by reefs.
Ancient mankind lived on isles near the Indo-Pacific coasts, rich in soil, fruit, fruit-bats, sea-birds, shellfish...going back and forth on occasion (during lower sea levels of the ice ages) by walking/wading/swimming/dugouts to continents
where the big predator cats lived.
Big cats couldn't survive on small islands, crocs might but avoid the
surf and sandy beaches, while sharks risk getting land-locked when
entering the shallow tidal lagoons. I think that slowly dugouts
eventually allowed human ancestors to over-run the continents through
the river systems into the savannas, with sturdy hulls protecting them
and storing their weapons of mass destruction (push-pole thrusting
spears, ballast of large pebbles for throwing), with tensile nets and
woven reed baskets slowly being developed.
--- In AAT@yahoogroups.com, "Dick Fischbeck"
>
> here are Fuller's words:
>
> http://www.bfi.org/EveryThing/everything_i_know3.htm
>
>
>
> [�]
>
> Unquestionably the great barrier reefs there break those
> enormous waves, and inside those lovely
> lagoons are full of fish and all kinds of eatables, and the very,
> very easy shoaling lovely sands
> and you could climb in and out of that as a baby practically, and
> on the shores coconuts falling
> down full of milk, and all kinds of things to eat, and no big
> animals to eat you so I came to the
> conclusion life being born naked and helpless, probably on the
> coral atolls, then began to have
> experience after experience with that water
>
> [...]
Boat vs backfloat while diving
Re: Atoll divers with bad joints due to mineral deficiency, boats & HV?
http://www.jstage.jst.go.jp/article/ase/114/1/114_1/_article
I'm guessing here, not enough data to be sure:
Atolls typically lack copper and iron which are needed for bone growth.
With that in mind, it seems likely to me that diving while often deeply hyperventilating might induce divers to stay at depth longer, increasing the chance of the bends, or Nitrogen micro-bubbles in the knee and other joints, with increased deterioration of the already poorly integrated tissues over time, especially if stressed (physical work done) soon after diving.
===========
[still working on this, not sure how much an effect mineral nutrients were in bone porosity vs HV-DCS]
1ma, He divers dove and backfloated and did not hyperventilate (as indicated by dense bones). Alternating partners diving/backfloating w/o HV produces no DCS N2 accumulation.
3.5ka Micronesian divers dove and boated and likely did hyperventilate (see Tarawa disease), possibly getting bent/DCS producing joint pain and possibly increased porosity in leg bones eventually, (as indicated by porous bones in their fossils derived from low Cu/Fe nutrients, but possibly also due to DCS). Individual or Unison diving/boating w/HV may produce DCS/bends/Tarawa disease.
Tuesday, August 21, 2007
What is a Mangrove? Manggi manggi
What is a mangrove?
The term 'mangrove', is used in the broad sense either to refer to the highly adapted plants found in tropical intertidal forest communities or the ecosystem itself. The term 'mangrove' may have been derived from a combination of the Malay word 'manggi-manggi', for a type of mangrove tree (Avicennia) and the Arabic 'el gurm', for the same, as 'mang-gurm'. As a word, it can be used to refer to a species, plant, forest or community!
A mangrove community
Nature, at the highest level of organisation, consists of the ecosphere which includes all living things (biosphere) together with non-living parts (atmosphere, hydrosphere, lithosphere). The next level is the biome which consists of groups of similar ecosystems over large geographic areas. Next is the ecosystem, which is a self-regulating community of organisms and their non-living environment.
The community, consists of interacting populations (single-species groups) of all the different plants and animals in the area, which in this case, is the mangrove. Thus essentially, the mangrove community is the biotic part of this ecosystem, which this book introduces.
Types of tropical rain forest
The term 'tropical rain forest' is used to describe forests of the ever-wet tropics or beyond, where there is, at most, minimal seasonal water shortage. These can be divided into dry-land and wetland rain forests. The first includes tropical lowland evergreen rain forest, which was the main type of forest covering Singapore, parts of which still exist in Bukit Timah Nature Reserve.
This also includes beach vegetation, which still exists along Singapore's east coast, Labrador Beach in the south, and the southern islands. Wetland rain forests include mangrove, brackish-water, freshwater and peat swamp forests. Of all these, only mangrove forests are under the direct influence of seawater.
Types of coastal habitats
The geological and environmental conditions of the shoreline result in different habitats. Exposure to currents and waves of the open sea results in the formation of rocky shore and sandy beaches. Sheltered shores, on the other hand, allow sediment from rivers and the sea to settle, and eventually become mangrove forests.
high tide (left) low tide (right)
http://mangrove.nus.edu.sg/guidebooks/text/1002.htm
The term 'mangrove', is used in the broad sense either to refer to the highly adapted plants found in tropical intertidal forest communities or the ecosystem itself. The term 'mangrove' may have been derived from a combination of the Malay word 'manggi-manggi', for a type of mangrove tree (Avicennia) and the Arabic 'el gurm', for the same, as 'mang-gurm'. As a word, it can be used to refer to a species, plant, forest or community!
A mangrove community
Nature, at the highest level of organisation, consists of the ecosphere which includes all living things (biosphere) together with non-living parts (atmosphere, hydrosphere, lithosphere). The next level is the biome which consists of groups of similar ecosystems over large geographic areas. Next is the ecosystem, which is a self-regulating community of organisms and their non-living environment.
The community, consists of interacting populations (single-species groups) of all the different plants and animals in the area, which in this case, is the mangrove. Thus essentially, the mangrove community is the biotic part of this ecosystem, which this book introduces.
Types of tropical rain forest
The term 'tropical rain forest' is used to describe forests of the ever-wet tropics or beyond, where there is, at most, minimal seasonal water shortage. These can be divided into dry-land and wetland rain forests. The first includes tropical lowland evergreen rain forest, which was the main type of forest covering Singapore, parts of which still exist in Bukit Timah Nature Reserve.
This also includes beach vegetation, which still exists along Singapore's east coast, Labrador Beach in the south, and the southern islands. Wetland rain forests include mangrove, brackish-water, freshwater and peat swamp forests. Of all these, only mangrove forests are under the direct influence of seawater.
Types of coastal habitats
The geological and environmental conditions of the shoreline result in different habitats. Exposure to currents and waves of the open sea results in the formation of rocky shore and sandy beaches. Sheltered shores, on the other hand, allow sediment from rivers and the sea to settle, and eventually become mangrove forests.
high tide (left) low tide (right)http://mangrove.nus.edu.sg/guidebooks/text/1002.htm
Sunday, August 19, 2007
Common Descent 3 by DDeden
Too Deep, Too Often, Too Soon? |
Quote:
| At Deeperblue.net Originally Posted by naiad  Totally OT now, but I am not sure about the role of air in underwater hearing. The most advanced orders of fish, Cypriniformes (carp, minnows, most coarse fish, danios, loaches etc.), Characiformes (tetras), Siluriformes (catfish), and Gymnotiformes (electric eels, knifefish), have a series of bones connecting the air bladder to the inner ear, allowing them to hear a much wider range of sounds than other fish. This must be important, because species which no longer need an air bladder for buoyancy (catfish, loaches), still have a small one for hearing, and in some cases for producing sounds. |
I think there's a freshwater fish that squirts water up at flying insects, I would guess that fish has good air-conduction aural capabilities (ear-air-sac), but also good water-conduction aural capabilities.
o0O0o0O0o0O0o `<8{(((>< o0O0o0O0o0O0o Regarding hearing underwater Too Deep, Too Often and Too Soon; although I think that ancestral humans dove at equatorial seashores in warm surface water, I've no doubt they encountered cool to cold water at depth and especially during coastal migrations farther from the equator. Evidence of ear exostosis (bony ear canal rings) has been found in a number of human fossils (Upper Nile River, Peruvian coast, Rome coldwater baths), this occurs due to sustained periodic exposure to cold water in the external ear canal over time. I think exostosis indicates mostly youthful single males habitually competing at greater depths without sufficient surface intervals to warm the ear canal and cerumen, over time this would produce bony accretion around the canal. This may indicate spearfishing more than mollusc hunting, since spearing requires a longer time at depth. However the fact that humans are no where nearly as hydrodynamic mammals like dolphins, sea lions, etc. indicates that spearfishing or "fast" chasing pelagic fish was not as common as "slow" diving for sessile/benthic foods (molluscs, oysters, marine snails, etc.). I'd guess spears were more jabbing-thrusting-prying tools, rather than shooting weapons; useful for crabs, flounder, immobile camoflaged octopi and such. AFAICT, paired archaic divers backfloated/dove in rotation at warm sunlit surface, the middle ear was warm-water filled and the external canal also warm-water filled, the earwax kept this warm water in place during the dive into the colder depths when the MDR was engaged, acting like thermal ear-plugs but not air-holding ear plugs. Although yet unconfirmed, I feel quite certain that simultaneously a similar thermo-retention system was employed in the sinunasal cavity and affiliated middle ears (via the eustacian tubes) by allowing warm surface water (larynx was valved shut) in and then closing the nasal passage via the swollen inferior concha (VR) and/or philtrum closure early during the dive into the cooler depths, preventing the "sinus-ice cream headache" otherwise sure to affect the diver (and which is now often covered by mask or hood) and alleviating the need for continuous equalizing with each elevation/pressure gradient.
So archaic human seashore divers/backfloaters used water-conduction hearing during their dive-foraging cycles, when hearing the dive partner was more significant than hearing prey or predator.
Allowing sun-warmed, UV-sterilized blood-temperature surface saline into the external ear, middle ear & sinonasal cavities just before diving deep meant that cold water at depth would trigger the facial and trigeminal nerves on the face maximizing the MDR, (unlike a full face mask & hood), yet (presumably) avoid the accompanying ice cream headache typical of prolonged cold water immersion of the bare face and forehead. This kept the brain warm at depth (conserving oxygen and energy), while the blood from the extremities moved towards the body core and the rest of the body acclimatised to the chilly temperature. Upon resurfacing, backfloating allowed maximum solar absorption, and blood returned to the small blood vessels of the sunwarmed extremities.
Ear extoses: Diving into the cold w/o retaining the warm Here's an article by DiBartolomeo JR 1979
Exostoses of the external auditory canal
Ann Otol Rhinol Laryngol Suppl 88 (6 Pt 2 Suppl 61) :2-20.
Exostosis of the external ear canal is a disease unique to man. It has been
identified in prehistoric man, affecting the aborigines of the N.American
continent. Aural exostoses are typically firm, sessile, multi-nodular bony
masses which arise from the tympanic ring of the bony portion of the
external auditory canal. These growths develop subsequent to prolonged
irritation of the canal. The large, primitive jaw of prehistoric man placed
great mechanical stress on the tympanic ring. Chronic aural suppuration seen
in the pre-antibiotic era was soon followed by exostoses.
Today, prolonged contact of the external ear canal with cold sea water is
the most prevalent cause (aquatic theory). As a result the disease is now
essentially limited to coastal regions. In this way we have seen exostoses
appear in different stages of the evolution of man as a result of mechanical,
chemical and now thermal irritation.
The author is an otolaryngologist in a coastal region.
In examining 11,000 patients during a 10-year period, 70 cases of
symptomatic exostoses of the external auditory canal were identified. The
incidence of exostoses was found to be 6.36 per 1000 patients examined for
otolaryngologic disease. It is a predominantly male disease. The development
of these "irritation nodules" is painless until the tenth year of aquatic
exposure to irritation, when symptoms of obstruction occur. The hearing loss
associated with exostoses is usually a conductive type, secondary to
occlusion of the canal by impacted cerumen or acute external otitis. The
results of studying the thermal characteristics of the body of water used
for such aquatic activities is presented.
identified in prehistoric man, affecting the aborigines of the N.American
continent. Aural exostoses are typically firm, sessile, multi-nodular bony
masses which arise from the tympanic ring of the bony portion of the
external auditory canal. These growths develop subsequent to prolonged
irritation of the canal. The large, primitive jaw of prehistoric man placed
great mechanical stress on the tympanic ring. Chronic aural suppuration seen
in the pre-antibiotic era was soon followed by exostoses.
Today, prolonged contact of the external ear canal with cold sea water is
the most prevalent cause (aquatic theory). As a result the disease is now
essentially limited to coastal regions. In this way we have seen exostoses
appear in different stages of the evolution of man as a result of mechanical,
chemical and now thermal irritation.
The author is an otolaryngologist in a coastal region.
In examining 11,000 patients during a 10-year period, 70 cases of
symptomatic exostoses of the external auditory canal were identified. The
incidence of exostoses was found to be 6.36 per 1000 patients examined for
otolaryngologic disease. It is a predominantly male disease. The development
of these "irritation nodules" is painless until the tenth year of aquatic
exposure to irritation, when symptoms of obstruction occur. The hearing loss
associated with exostoses is usually a conductive type, secondary to
occlusion of the canal by impacted cerumen or acute external otitis. The
results of studying the thermal characteristics of the body of water used
for such aquatic activities is presented.
DDeden (Thanks MV at AAT)
__________________
"Dive well and come up for more"
"Dive well and come up for more"
Friday, August 17, 2007
Common Descent 2 by DDeden
I think human ancestors a million years ago dove daily for food (clams etc.) at tropical seashores, which is why we don't look like our closest genetic cousins the chimps. These human seashore ancestors did not hyperventilate before diving, did not pack or wear fins, masks or
scuba. They dove alternatively in male-female diving teams; while one backfloated above in the very warm sunlight lagoon surface water, the other dove down into the cool dark blue along reefs collecting sessile shellfish, repeating this over and over, switching roles, until they got their fill of seafood, then went back to the beach for a coconut cocktail.
This would require that at depth, the water was cool, not hot, otherwise the [MDR] Mammalian Divers Reflex would not fully engage, which means oxygen would not be conserved well. The MDR was an essential energy-saving part of the dive cycle; whereas during back-floating at the surface the opposite occurred, "wasting" [O2] oxygen in order to remove excess [N2] Nitrogen and [CO2] Carbon Dioxide and accumulated waste products. [SEE NOTE AT POST BOTTOM] Urinating during the dive, and sweating at
the sunny surface removed urea (which contained Nitrogen), and humming at the surface removed [NO] Nitric Oxide from the sinuses (killing waterborne bacteria in the water which was allowed into the nasal/sinus/middle ear cavities during the dive to avoid equalizing constantly). This humming at the surface by the backfloater (likely with a chest-held infant that was clinging to the long head hair or beard) was the first lullaby, the NO-enriched air was inhaled by the infant
(who could not hum (until later first saying "mama" and could not yet shed tears, so the parent's NO provided antibiotic protection to the infant's face), and the humming could be heard by the dive partner below (not distracted by noisy scuba bubbles), who then made tongue clicks which was heard by the backfloater, this "hydrosonic" communication was the original form of sustained speech, (which later derived into the vowels and consonants) allowed non-visual contact between the partners, the sound waves carried efficiently through water and the very dense occiput (the skull plate on back of head which in ancient humans was the most dense bone in the body, perfect for sound transmission via bone conduction as found in dolphins and sea cows).
So, "too deep. too often, too soon", according to the archaic diving cycle was not an issue, as long as the diving partners alternated consistently, allowing gas exchange at the surface. I assume max depth was 100 m, but much more likely 30m max for adult males, 15m for females repetitively, and probably often less. No diving in fast current, cold surface water, hot depth water, big surf or rainy weather. [They don't teach all this in kindergarten or sunday school, but I think it's accurate.] :-) DDeden
KP @ Deeperblue.net) i'm buying most of it but since i can't make loud clicking sounds with my tongue while having the ease of air around - i can't imagine being able to do it loud enough underwater [UW] for someone's skull plate to feel the reverberation. Perhaps those (archaic) folks had larger sinus cavities and mouths as well? kp
(DD) Neandertals living on the coasts had huge sinuses. According to some anthropologists, their voices (according to fossil anatomy, hyoid bone structure) probably had somewhat high-pitched during speech compared to modern folks.
Perhaps their mouths were larger (they lacked chins), I don't think that would matter so much. I think their visible external ears (pinnae) were smaller than ours, maybe even smaller than gorilla or gibbon ears, but pinnae don't fossilize so it's unknown.
Still water carries sound far far better than air does, that's why both dolphin clicking and humpback whale song can be heard at long distances. For the same reason, solid flat ground (savanna) carries sound. Bull elephants make thunderous bass trumpeting sounds that carry for miles, the females hear the sounds through their FEET via bone conduction from the solid ground, NOT primarily through their huge external ears via air conduction. Air simply doesn't carry sound very effectively. Human hearing is 50% air conduction, 50% bone conduction. In water, only bone conduction functions.
As long as the backfloater is on the still surface with the ears and occiput in the water, and the entire ear (inner, middle and outer ear) is fluid filled (in a lagoon, not in open sea with loud surf), and the diver's ears are also fluid filled, any clicking or humming sounds will carry a good distance. In air, clicking doesn't carry very far, (though the Khoisan people retain clicks in their language), but dolphins prove that UW clicking is both effective and efficient communication.
The problem with hearing UW is presence of air in bone cavities, once air is replaced with water, sounds carry well, no need for loud clicks, even soft clicks carry a ways. Simply ticking the teeth together works too for a short distance. Some shrimp, crabs and fish make clicking sounds in various ways. There's no loss of air in clicking, unlike vocal speech or humming.
Caution, this stuff is potentially DANGEROUS if you don't know what you're doing. It's still just theoretical, I haven't tested it yet, being poor and stuck in Nor Cal by cold water, I need to get down to the tropics to do empirical research.---
MV: Makes a lot of sense to me, except the surface sweating: do we have more sweat glands on the abdomen?
DD: No, fewer. Eccrine sweating is a whole body phenomenon. However, the top 6 inches (15cm?) of sunwarmed lagoon equatoreal water is very warm at midday. Therefore the whole body sweats AFAIK, but the body is not appreciably cooled unless a breeze is present. Do you think a backfloater would benefit from having many sweat glands on the abdomen? UV light is anti-biotic, it can damage eccrine sweat glands even in melanized people IIRC. Do Phocids have sweat glands more dorsally or ventrally on abdomens or flippers?
btw, I just read (Discover or Nature mag.) that urea (fresh) is anti-fungal and anti-biotic. That confirms my earlier speculation (w/Elaine etc.) that UREA, in addition to the cathlicidens (spelling), defensins and dermcidin in eccrine sweat, ALL are components of the biochemical antibiotic armor in humans. What I don't know is whether urea converts back to ammonia in the presence of air or seawater. I know that urine smells ammonia-like after mixing with air, but is that uric acid or urea converting to ammonia? Ammonia is highly toxic both to humans and microbes.
the reduction of the olfaction in hominoids and further in Homo, was it associated with the reduction of the bony conchae/turbinates as well? I would expect so, since semivertical floating would select for lightening of the protruding nose, while backfloating would also select for lightweight nose as long as some structural integrity was present. I'd expect that the LCA Hominoid - LCA Hominid had a relatively low density skull and or skull bone thinning as opposed to modern chimps & gorillas. This only changed with Homo erectus. (So apiths would not be
expected to have thick skulls except the mandibles for chewing). Significantly, those animals with large protruding noses (probosis monkey, tapir, elephant) do not have hyperventilatory air sacs but do have tails, they employ a different form of vocalization resonance than tail-less apes, and do not float semivertically, but rather swim or wade. Macaques seem split, with long tail divers and short tail waders/floaters? AFAIK only the floaters have enlarged lar air sacs
(need to verify). I think the pinnae were smaller, and this was retained in gorillas,
gibbons, but later enlarged in the chimps, humans due to heavier predation pressure later on (more savanna type environments).
NOTE: DT: Do you mean that the NO and urine remove excess Nitrogen that was absorbed from air?
If so then I don't see how that is possible, N2 is inorganic and needs to be "fixed" inorder to be metabolized, as far as I know mostly unicellular organisms have Nitrogen fixation capabilities and we definitely don't... and I doubt symbiotic bacterias can produce enough during diving for it to make any difference....
DD: thanks much for checking.
I erred, mixing (apples) inert N2 from air, and (oranges) Nitrogen compounds from high protein molluscs. I'd thought that N2 was not easily absorbed into blood, that scuba at depth increased absorption, but that a significant part came from high-protein foods, and that adding N2 at depth was just a part of it, the straw that broke the camel's back.
Do you know whether, upon switching from inhaling air to O2, does blood N2 drop down to zero? If so, would digestion of hi-protein food rich in nitrogen compounds (molluscs) cause an increase in N2 in the body, especially in the blood? That is what I thought happened, which is why I thought of excretion. I was thinking of other chemicals which end in the bloodstream (drugs etc.).
Anyway, I'll review and edit my post, for now i'll just note it.
Note on NO production sources: From Wikipedia: (KM at AAT)
"In the body, nitric oxide (the 'endothelium-derived relaxing factor',
or 'EDRF') is synthesized from arginine
Arginine - Wikipedia, the free encyclopedia and oxygen
Oxygen - Wikipedia, the free encyclopedia by various nitric oxide synthase
Nitric oxide synthase - Wikipedia, the free encyclopedia (NOS) enzymes
Enzyme - Wikipedia, the free encyclopedia and by sequential reduction of inorganic nitrate."
scuba. They dove alternatively in male-female diving teams; while one backfloated above in the very warm sunlight lagoon surface water, the other dove down into the cool dark blue along reefs collecting sessile shellfish, repeating this over and over, switching roles, until they got their fill of seafood, then went back to the beach for a coconut cocktail.
This would require that at depth, the water was cool, not hot, otherwise the [MDR] Mammalian Divers Reflex would not fully engage, which means oxygen would not be conserved well. The MDR was an essential energy-saving part of the dive cycle; whereas during back-floating at the surface the opposite occurred, "wasting" [O2] oxygen in order to remove excess [N2] Nitrogen and [CO2] Carbon Dioxide and accumulated waste products. [SEE NOTE AT POST BOTTOM] Urinating during the dive, and sweating at
the sunny surface removed urea (which contained Nitrogen), and humming at the surface removed [NO] Nitric Oxide from the sinuses (killing waterborne bacteria in the water which was allowed into the nasal/sinus/middle ear cavities during the dive to avoid equalizing constantly). This humming at the surface by the backfloater (likely with a chest-held infant that was clinging to the long head hair or beard) was the first lullaby, the NO-enriched air was inhaled by the infant
(who could not hum (until later first saying "mama" and could not yet shed tears, so the parent's NO provided antibiotic protection to the infant's face), and the humming could be heard by the dive partner below (not distracted by noisy scuba bubbles), who then made tongue clicks which was heard by the backfloater, this "hydrosonic" communication was the original form of sustained speech, (which later derived into the vowels and consonants) allowed non-visual contact between the partners, the sound waves carried efficiently through water and the very dense occiput (the skull plate on back of head which in ancient humans was the most dense bone in the body, perfect for sound transmission via bone conduction as found in dolphins and sea cows).
So, "too deep. too often, too soon", according to the archaic diving cycle was not an issue, as long as the diving partners alternated consistently, allowing gas exchange at the surface. I assume max depth was 100 m, but much more likely 30m max for adult males, 15m for females repetitively, and probably often less. No diving in fast current, cold surface water, hot depth water, big surf or rainy weather. [They don't teach all this in kindergarten or sunday school, but I think it's accurate.] :-) DDeden
KP @ Deeperblue.net) i'm buying most of it but since i can't make loud clicking sounds with my tongue while having the ease of air around - i can't imagine being able to do it loud enough underwater [UW] for someone's skull plate to feel the reverberation. Perhaps those (archaic) folks had larger sinus cavities and mouths as well? kp
(DD) Neandertals living on the coasts had huge sinuses. According to some anthropologists, their voices (according to fossil anatomy, hyoid bone structure) probably had somewhat high-pitched during speech compared to modern folks.
Perhaps their mouths were larger (they lacked chins), I don't think that would matter so much. I think their visible external ears (pinnae) were smaller than ours, maybe even smaller than gorilla or gibbon ears, but pinnae don't fossilize so it's unknown.
Still water carries sound far far better than air does, that's why both dolphin clicking and humpback whale song can be heard at long distances. For the same reason, solid flat ground (savanna) carries sound. Bull elephants make thunderous bass trumpeting sounds that carry for miles, the females hear the sounds through their FEET via bone conduction from the solid ground, NOT primarily through their huge external ears via air conduction. Air simply doesn't carry sound very effectively. Human hearing is 50% air conduction, 50% bone conduction. In water, only bone conduction functions.
As long as the backfloater is on the still surface with the ears and occiput in the water, and the entire ear (inner, middle and outer ear) is fluid filled (in a lagoon, not in open sea with loud surf), and the diver's ears are also fluid filled, any clicking or humming sounds will carry a good distance. In air, clicking doesn't carry very far, (though the Khoisan people retain clicks in their language), but dolphins prove that UW clicking is both effective and efficient communication.
The problem with hearing UW is presence of air in bone cavities, once air is replaced with water, sounds carry well, no need for loud clicks, even soft clicks carry a ways. Simply ticking the teeth together works too for a short distance. Some shrimp, crabs and fish make clicking sounds in various ways. There's no loss of air in clicking, unlike vocal speech or humming.
Caution, this stuff is potentially DANGEROUS if you don't know what you're doing. It's still just theoretical, I haven't tested it yet, being poor and stuck in Nor Cal by cold water, I need to get down to the tropics to do empirical research.---
MV: Makes a lot of sense to me, except the surface sweating: do we have more sweat glands on the abdomen?
DD: No, fewer. Eccrine sweating is a whole body phenomenon. However, the top 6 inches (15cm?) of sunwarmed lagoon equatoreal water is very warm at midday. Therefore the whole body sweats AFAIK, but the body is not appreciably cooled unless a breeze is present. Do you think a backfloater would benefit from having many sweat glands on the abdomen? UV light is anti-biotic, it can damage eccrine sweat glands even in melanized people IIRC. Do Phocids have sweat glands more dorsally or ventrally on abdomens or flippers?
btw, I just read (Discover or Nature mag.) that urea (fresh) is anti-fungal and anti-biotic. That confirms my earlier speculation (w/Elaine etc.) that UREA, in addition to the cathlicidens (spelling), defensins and dermcidin in eccrine sweat, ALL are components of the biochemical antibiotic armor in humans. What I don't know is whether urea converts back to ammonia in the presence of air or seawater. I know that urine smells ammonia-like after mixing with air, but is that uric acid or urea converting to ammonia? Ammonia is highly toxic both to humans and microbes.
the reduction of the olfaction in hominoids and further in Homo, was it associated with the reduction of the bony conchae/turbinates as well? I would expect so, since semivertical floating would select for lightening of the protruding nose, while backfloating would also select for lightweight nose as long as some structural integrity was present. I'd expect that the LCA Hominoid - LCA Hominid had a relatively low density skull and or skull bone thinning as opposed to modern chimps & gorillas. This only changed with Homo erectus. (So apiths would not be
expected to have thick skulls except the mandibles for chewing). Significantly, those animals with large protruding noses (probosis monkey, tapir, elephant) do not have hyperventilatory air sacs but do have tails, they employ a different form of vocalization resonance than tail-less apes, and do not float semivertically, but rather swim or wade. Macaques seem split, with long tail divers and short tail waders/floaters? AFAIK only the floaters have enlarged lar air sacs
(need to verify). I think the pinnae were smaller, and this was retained in gorillas,
gibbons, but later enlarged in the chimps, humans due to heavier predation pressure later on (more savanna type environments).
NOTE: DT: Do you mean that the NO and urine remove excess Nitrogen that was absorbed from air?
If so then I don't see how that is possible, N2 is inorganic and needs to be "fixed" inorder to be metabolized, as far as I know mostly unicellular organisms have Nitrogen fixation capabilities and we definitely don't... and I doubt symbiotic bacterias can produce enough during diving for it to make any difference....
DD: thanks much for checking.
I erred, mixing (apples) inert N2 from air, and (oranges) Nitrogen compounds from high protein molluscs. I'd thought that N2 was not easily absorbed into blood, that scuba at depth increased absorption, but that a significant part came from high-protein foods, and that adding N2 at depth was just a part of it, the straw that broke the camel's back.
Do you know whether, upon switching from inhaling air to O2, does blood N2 drop down to zero? If so, would digestion of hi-protein food rich in nitrogen compounds (molluscs) cause an increase in N2 in the body, especially in the blood? That is what I thought happened, which is why I thought of excretion. I was thinking of other chemicals which end in the bloodstream (drugs etc.).
Anyway, I'll review and edit my post, for now i'll just note it.
Note on NO production sources: From Wikipedia: (KM at AAT)
"In the body, nitric oxide (the 'endothelium-derived relaxing factor',
or 'EDRF') is synthesized from arginine
Arginine - Wikipedia, the free encyclopedia and oxygen
Oxygen - Wikipedia, the free encyclopedia by various nitric oxide synthase
Nitric oxide synthase - Wikipedia, the free encyclopedia (NOS) enzymes
Enzyme - Wikipedia, the free encyclopedia and by sequential reduction of inorganic nitrate."
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